<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <style>
        button {
            background-color: rgba(45, 6, 105, 0);
            width: 200px;
            height: 200px;
            color: skyblue;
        }
    </style>
    <title>Document</title>
</head>

<body>
    <button>我是一个盒子</button>
    <script>
        document.querySelector('button').onclick = function() {
            alert('么么哒')
            alert('hello')
        }
    </script>
</body>

</html>